PS/ZnO nanocomposite films

The TEM, high-resolution TEM and FESEM images of ZnO nanoparticles and FESEM images of PS/ZnO nanocomposite films (Figure 12.9) show the surface morphology. The average particle diameters determined from the XRD peaks using the Debye-Scherrer formula are found to be close to those based on TEM and FESEM analysis. 

Figure 12.10 UV-visible absorption spectra of PS and PS/ZnO nanocomposite films.

Figure 12.8 PL emission spectra of (i) ZnO and (ii) PS andPS/ZnO nanocomposite films (a, b and c - PS/ZnO composite films with 5,10, and 20 wt% of ZnO, respectively).

The fascinating properties exhibited by nanoparticles, such as blue shift of the absorption spectrum, size-dependent luminescence, etc., are various manifestations of the so-called quantum confinement effect. These unique properties make ZnO a promising candidate for applications in optical and optoelectronic devices [35-38]. Polymer-based nanocomposites are the subject of considerable research due to the possibility of combining the advantages of both polymers and nanoparticles. There are several applications of polymeric nanocomposites based on their optical, electrical and mechanical properties. Further, nanocrystals dispersed in suitable solid hosts can be stabilized for long periods of time. Polystyrene (PS)— an amorphous, optically clear thermoplastic material, which is flexible in thin-film form—is often chosen as a host matrix because of its ideal properties for investigating optical properties. It is one of the most extensively used plastic materials, e.g., in disposable cutlery, plastic models, CD and DVD cases, and smoke-detector housings. 

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